<!doctype html> 
<html> 
<head> 
    <meta charset="utf-8"> 
    <title></title> 
</head>
<body>
<script type="text/javascript">
	
var a = new String('abc');
var b = 'abc';
var c = function (){alert(b+a)};
var d = [a,b,c];
a = b = c = null;
d[2]();//'abcabc'
alert(d);//['abc','abc',function (){alert(b+a)}];

</script>
</body>
</html>